Human computation, involving human responses in a computer system as part of the computation, is used for many different tasks for example in generating information from online game data.
A game called the ESP game has been created where images are tagged with information by players of an image description guessing game. The game makes it possible to tag images through the Google Image Labeler game.
Using humans to add information about things that machines don't understand has been proven to be very powerful. The ESP game follow up, Peekaboom, was played by 27,000 people in the first 4 months, generating 2,100,000 pieces of data.
The feature of labelling media, for example pictures, with a position is used in many applications like Flickr, Panoramio, etc. The other way around, labeling of positions with media, is not a well used concept. However, media files being descriptive of geographical positions are believed to be highly demanded in the future, for example for use in online map applications, such as Google Earth. The media files that describe a certain location could then be presented to a user expressing an interest in that location, for example by indicating the location on the map.
Generating media files such as pictures, texts, audio and video clips that are descriptive of different geographical positions is time consuming. Therefore, it is desirable to involve the public in the process of generating such media. For example, the public may be encouraged to use their mobile phones to take photos that are descriptive of a geographical position, and upload the pictures to a web server for use in, e.g., an online map application.
However, as is often the case when using user-generated material in applications, it is difficult to guarantee that the quality of the user-generated media files fulfils the requirements needed in order for the application to be truly useful and appreciated. Or, in other words, it is difficult to ensure that a user-generated media file is truly descriptive of a geographical position of which it is alleged to be descriptive by the user submitting it.
Thus, a problem associated with labeling of positions with media is how to determine whether a certain media file is truly descriptive of a geographical position.